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Dextrin-microencapsulated porphyrin: luminescent properties
Priscilla Paiva Luz1, Cláudio Roberto Neri, Osvaldo Antonio Serra
1Chemistry Department of FFCLRP, University of São Paulo, Bandeirantes Av. 3900, 14040-901 Ribeirão Preto, Brazil.
Annals of the New York Academy of Sciences
|July 4, 2008
Summary
Encapsulating meso-tetrakis(4-sulphonatophenyl) porphyrin (TPPS(4)) into dextrin microspheres using ultrasonic spray-drying prevents aggregation. This method enhances luminescence intensity for potential photodynamic therapy applications.
Area of Science:
- Materials Science
- Photochemistry
- Biomedical Engineering
Background:
- Porphyrin aggregation in aqueous solutions negatively impacts photophysical properties.
- Aggregation hinders the use of porphyrins as photosensitizers in treatments like photodynamic therapy (PDT).
- Polymeric encapsulation offers a strategy to maintain porphyrins in their monomeric form.
Purpose of the Study:
- To investigate the microencapsulation of meso-tetrakis(4-sulphonatophenyl) porphyrin (TPPS(4)) using ultrasonic spray-drying.
- To characterize the morphology and photophysical properties of encapsulated TPPS(4).
- To compare the properties of encapsulated TPPS(4) with a physical blend.
Main Methods:
- Ultrasonic spray-drying technique for microencapsulation of TPPS(4) into dextrin microspheres.
- Scanning electron microscopy (SEM) for morphological characterization.
- Photophysical property analysis, including luminescence intensity measurements.
Main Results:
- Successful microencapsulation of TPPS(4) within dextrin microspheres was achieved.
- Scanning electron microscopy confirmed the spherical morphology of the microspheres.
- Encapsulated TPPS(4) exhibited significantly higher luminescence intensity compared to physical blends.
Conclusions:
- Ultrasonic spray-drying is an effective method for encapsulating TPPS(4) into dextrin microspheres.
- Encapsulation prevents porphyrin aggregation, preserving and enhancing its photophysical properties.
- The enhanced luminescence of encapsulated TPPS(4) shows promise for improved photodynamic therapy efficacy.
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